I found this support forum post but the solution provided doesn’t work.
Edit (thanks to @moreeni@lemm.ee for the Stack Exchange link):
Solution - Go to Settings -> Home -> Enable Shortcuts -> Go to a new tab -> Google will be pinned by default, hover over the Google icon -> Click on the 3 dots menu -> Unpin
If you wouldnt mind getting rid of Google search entirely … settings, search, select Google, remove. I assume there is nothing to pin after that?